The present invention relates to systems and methods for treating process material and, more particularly, to systems and methods for treating municipal solid waste material, medical waste material, reclaimed paper and the like.
As a result of increasing scarcity of landfills and more stringent environmental regulations, efforts have been made to reduce the volume of process material, such as municipal solid waste (“MSW”) and paper material, such as newsprint and other reclaimed and recycled paper products as a step in the process of disposing of the material, either by depositing it in landfills, incinerating it or recycling it.
Systems and methods have been developed to break down such material for disposal, or in the case of paper products, use as insulation.
One of the disadvantages of systems of the prior art is that they fail to make maximum most efficient use of the energy used in these systems. Prior art systems generally release copious quantities of steam during the cool-down cycle, and the release of steam is a significant energy cost. Accordingly, there remains a need for waste treatment systems that make more efficient use of energy in their operation.
Another disadvantage of systems of the prior art is that they have been less than completely satisfactory in their efficient and complete use and treatment of water that is contained in the waste mass or that is otherwise supplied to the waste treatment autoclave. In addition, efficient use of water is also required where operation of waste treatment systems is desired in areas where suitable water supplies are scarce or unavailable, or otherwise where waste water cannot be legally or economically released. There remains a need for waste treatment systems that may more efficiently use and recycle water, especially the “contact” water from condensate that was in contact with waste and which can even be operated in areas of water scarcity and/or where water should not be released.
Another disadvantage of systems of the prior art is that the fibrous “product” of the waste autoclave process is a clean cellulose, for which to date there is little commercial market. Some systems exist that will oxidize the cellulose thus releasing energy; there remains a need for an efficient system to convert this energy into saleable commodities.
Another disadvantage of systems of the prior art is that the autoclave process releases small quantities of volatile organics. An effective and efficient system to separate volatiles (and air) from contact steam is needed.
The present invention accordingly represents an improvement over prior art apparatus and methods, such as those described in U.S. Pat. Nos. 5,540,391; 5,116,363; 5,253,764; 5,190,226; 5,361,994; 5,427,650; 5,407,809; and 6,397,492, and in published European Patent Application No. 02758620.5; all of which are incorporated herein by reference. The present invention also represents an improvement relating to and which may be used in conjunction with the inventions described in co-pending application Ser. Nos. 11/122,341, 11/716,101, 11/981,144, 61/123,351, 61/195,791, 12/313,911 and PCT/US06/16773 that are hereby incorporated in their entirety by reference.
The present invention also relates to and may be used in conjunction with co-pending application Ser. No. 12/315,258, which is hereby incorporated in its entirety by reference and which focuses on the steam/water recycling aspects of a total waste-to-energy system.